496 NOTICE OF UNDESCRIBED FOSSILS 



Art. IV. — A Notice of some undescribed Organic Remains which 

 have recently been discovered in the London Clay Formation. By 

 Nathaniel Thomas Wetherell, Esq., F.G.S., M.R.C.S., &c. 



The fossil bodies represented in plates viii. and ix. of the 

 Supplementary Illustrations, were found between Euston 

 Square and Kilburn, in the excavations for the London and 

 Birmingham Kail-road. They occurred at depths varying 

 from twelve to forty feet; London clay being exposed at 

 this place within a few feet of the vegetable mould. When 

 I first examined these fossils, they appeared so very different 

 from any I had previously seen, that I determined to lose no 

 time in obtaining as good a series of them as possible. There 

 exists among several of my geological friends a difference of 

 opinion as to their real nature ; some having regarded them 

 as Spongites, while others have supposed them to be of ve- 

 getable origin. For my own part I am quite doubtful to what 

 class they belong, and therefore prefer leaving the question 

 open to further investigation, before proposing any generic 

 name. The two copper plates which accompany this notice 

 have been engraved by Mr. J. De C. Sowerby, and I cannot 

 help observing that he has delineated the figures very accu- 

 rately. I will now proceed to give some account of a few of 

 the specimens, but I must first state that I employ botanical 

 terms, with the view of making my descriptions more clearly 

 understood. 



One of the specimens (plate ix. fig. 1) is leaf-shaped, flat- 

 tened, and curved to one side ; width four inches and three 

 quarters, length uncertain, owing to the upper part having 

 been broken off; thickness half an inch. The whole of the 

 anterior and posterior surfaces is studded with a profusion of 

 small bodies, for the most part of an oval form, and a few of 

 them have a furrow down the middle. In one part these bo- 

 dies are nearly cylindrical, and so regularly placed in relation 

 to each other, that they appear like the lateral arms of a Pent- 

 acrinite. 



Fig. 1 a. — Oviform bodies magnified, some of them show- 

 ing the longitudinal furrow. 



Fig. 2. — A fine portion of a large stem dividing into four 

 branches, arising from which may be distinctly seen several 

 smaller ones, diverging in different directions. Like fig. 1 

 this specimen is covered with the small oviform bodies. 



Fig. 3 is also a fragment of a stem, with the bases of two 

 branches, the upper one of the size of a goose quill, the low- 

 er one much smaller. Besides having the same kind of ovi- 



